反应详情

To 230 mg of the 2-benzylidenehydrazono-3-ethoxycarbonylmethyl-1-methoxycarbonylmethylimidazolidin-4-one obtained in the above Referential Example 2 was added 10 ml of 0.5N hydrochloric acid and the mixture was steam-distilled for 40 minutes. After cooling, the reaction mixture was concentrated under reduced pressure and the residue was charged on silica gel column chromatography, followed by elution with a mixed solvent of chloroform and ethyl acetate (1:2 (v/v)). Thus 60 mg of 7-ethoxycarbonylmethyl-1,4,5,7-tetraazabicyclo[4.3.0]nonan-5-en-3,8-dione was obtained.

1. distillationthe mixture was steam-distilled for 40 minutes
2. temperatureAfter cooling
3. concentrationthe reaction mixture was concentrated under reduced pressure
4. additionthe residue was charged on silica gel column chromatography
5. washfollowed by elution with a mixed solvent of chloroform and ethyl acetate (1:2 (v/v))